Nameless fields in Go structs?

Question

package main  import "fmt"  type myType struct {     string }  func main() {     obj := myType{"Hello World"}      fmt.Println(obj) } 

What is the purpose of nameless fields in structs?

Is it possible to access these fields like you can do with named fields?

Answer 1

No disrespect to the chosen answer, but it did not clarify the concept for me.

There are two things going on. First is anonymous fields. Second is the "promoted" field.

For anonymous fields, the field name you can use is the name of the type. The first anonymous field is "promoted", which means any field you access on the struct "passes through" to the promoted anonymous field. This shows both concepts:

package main  import (     "fmt"     "time" )  type Widget struct {     name string }  type WrappedWidget struct {     Widget       // this is the promoted field     time.Time    // this is another anonymous field that has a runtime name of Time     price int64  // normal field }  func main() {     widget := Widget{"my widget"}     wrappedWidget := WrappedWidget{widget, time.Now(), 1234}      fmt.Printf("Widget named %s, created at %s, has price %d\n",         wrappedWidget.name, // name is passed on to the wrapped Widget since it's                             // the promoted field         wrappedWidget.Time, // We access the anonymous time.Time as Time         wrappedWidget.price)      fmt.Printf("Widget named %s, created at %s, has price %d\n",         wrappedWidget.Widget.name, // We can also access the Widget directly                                    // via Widget         wrappedWidget.Time,         wrappedWidget.price) } 

Output is:

Widget named my widget, created at 2009-11-10 23:00:00 +0000 UTC m=+0.000000001, has price 1234 Widget named my widget, created at 2009-11-10 23:00:00 +0000 UTC m=+0.000000001, has price 1234```